The present invention relates to a slide door structure of a vehicle which has a slide door to slide in a vehicle longitudinal direction at a side of a vehicle body.
Conventionally, the slide door which slides in the vehicle longitudinal direction to open and close a door opening is well known as a side door provided at the side of the vehicle body (see Japanese Patent Laid-Open Publication No. 9-2065, for example). This slide door has been used well in so-called one-box type of vehicles.
In such vehicles, a rail (guide rail) extending in the vehicle longitudinal direction is disposed at the side portion of the vehicle, and rollers to rotate and move along the guide rail are provided at the slide door. Thereby, the slide door slides in the vehicle longitudinal direction so as to open or close as the rollers rotate and move along the guide rail.
In general, the guide rail comprises a pair of guide face portions which face to each other vertically, a fixing face portion which connects respective inside end portions of the guide face portions and is to be fixed to the side portion of the vehicle body, and an opening which is formed between respective outside end portions of the guide face portions. Thus, the guide rail has a cross section which is of a U shape with its outside end opening outward. The rollers are rotatably supported at a support member which extends through the above-described opening between the guide face portions of the guide rail, so that the rollers can rotate and move along the guide rail, having a vertical guidance by the guide face portions.
In the above-described vehicle equipped with the slide door, in case a force acts on the slide door outward in the vehicle width direction when the slide door is in a closed state, the outward force is applied to the rollers via a door body of the slide door. This outward force acts on the pair of guide face portions of the guide rail. Herein, in case the outward force is relatively large, there may occur a so-called expansion of guide-rail end in which the above-described opening between the guide face portions of the guide rail expands.
This expansion of guide-rail end may cause an improper outward displacement of the roller, so that there is a concern that the rollers would be derailed off the guide roller in an extreme case. The greater the above-described outward displacement of the rollers becomes, the greater a gap between the side face of the vehicle body and the door body of the slide door becomes when the slide door is in the closed state. Consequently, there is a problem in that the stable support of the slide door would deteriorate.
The slide door is generally configured to engage with the vehicle-body side via a latch/striker mechanism, a so-called catcher/pin mechanism, or the like when the slide door is in the closed state. Herein, in case the above-described outward-acting load is considerably large, the side portion of the vehicle body would deform partially. Consequently, the above-described mechanism could not stand the load properly, so that there is a problem in that the gap between the side face of the vehicle body and the slide door would become improperly large.